Características sedimentológicas da plataforma continental interna rasa na porção central do litoral paranaense

Abstract

The aim of this work aims at knowing the shallow inner continental shelf between 5 and 15 m water depths of the State of Paraná between the Guaratuba (south) and Paranaguá (north) estuaries. Bathymetric data, grain size analysis and carbonate and organic matter rates of bottom sediments samples allowed to make thematic charts of this deposicional environment. The predominance of fine sand is quite large; despite the mean grain size of the samples varies (coarse silt to coarse sand). It was identified five different sediment patterns at the study area: i) fine and very fine sands of the Paranaguá Estuarine Complex south mouth tide delta; ii) bimodal very fine sand with 10 to 40% rates of silt and clay that occurs near the coastline between 5 and 10 m water depths; iii) unimodal medium and coarse sand sediments; iv) fine sand sediments between 10 and 15 m water depths, unimodal but different from the delta fine sands because the distributions in more Ø intervals; v) fine and very fine sands of the beach braking bars zone.